I think some clarification of the "can" in 3.2 is required. Maybe say something like "the handling of file input fields that allow multiple files to be specified varies between browsers. Some send these as sets of files (wrapping all the parts for the files in one multipart/mixed), some just send multiple form-data parts with the same "name" attribute. HTML5 specifies the latter behavior."
I think some clarification of the "can" in 3.2 is required. Maybe say something like "the handling of file input fields that allow multiple files to be specified varies between browsers. Some send these as sets of files (wrapping all the parts for the files in one multipart/mixed), some just send multiple form-data parts with the same "name" attribute. HTML5 specifies the latter behavior."
(See:) http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#multipart-form-data